Algoritmo de SLAM en un robot móvil gobernado por una interface cerebro-computadora

En este trabajo se presenta la aplicación de un algoritmo de Localización yMapeo Simultáneos (SLAM, por sus siglas en inglés de Simultaneous Localization andMapping) en una Interface Cerebro-Computadora (ICC) que gobierna la navegación de unrobot móvil. La ICC consta de un panel con lugares y funciones predefinidas dentro de unambiente conocido. El paciente, mediante sus señales electroencefálicas, puede elegir avoluntad desde el panel de control, la función a ejecutar o el destino a alcanzar por el robotmóvil. El algoritmo de SLAM permite generar mapas de nuevos entornos. Estos mapas, sonsegmentados y adicionados a la ICC, ampliando así las opciones del panel. Con los mapasobtenidos es posible generar trayectorias de navegación para el robot móvil. Acompañaneste trabajo, los resultados experimentales obtenido

Tuberous sclerosis with pulmonary lymphangioleiomyomatosis and renal angiomyolipomas. Computed tomographic findings: a case report

The authors describe a case of a 31-year-old female with tuberous sclerosis, a genetic, rare, variably expressed disease. Clinical symptoms were chest pain, and progressive dyspnea. Computed tomography scan of the chest showed bilateral, diffuse, small thin-walled cysts scattered throughout the lungs characteristic for pulmonary lymphangioleiomyomatosis. Computed tomography scan of the abdomen revealed enlarged, heterogeneous kidneys, with low density tumors corresponding to angiomyolipomas. Pulmonary lymphangioleiomyomatosis and bilateral renal angiomyolipomas are some presentations of tuberous sclerosis and the coexistence of both conditions may cause devastating morbidity and mortality

Risk factors for hepatitis C virus infection among blood donors in southern Brazil: a case-control study

BACKGROUND: In Brazil, it is estimated that between 2.5 and 4.9% of the general population present anti-hepatitis C virus (HCV) antibodies, which corresponds to as many as 3.9 to 7.6 million chronic carriers. Chronic liver disease is associated with HCV infection in 20% to 58% of the Brazilian patients. The objective of this case-control study was to investigate the risk factors for presence of anti-HCV antibody in blood donors in southern Brazil. METHODS: One hundred and seventy eight blood donors with two positive ELISA results for anti-HCV were cases, and 356 controls tested negative. A standardized questionnaire was used to collect data concerning demographic and socioeconomic aspects, history of previous hepatitis infection, social and sexual behaviors, and number of donations. Variables were grouped into sets of hierarchical categories. Cases and controls were compared using logistic regression, odds ratios, and 95% confidence intervals. The statistical significance of the associations was assessed through likelihood ratio tests based on a P value < 0.05. RESULTS: The prevalence of anti-HCV among blood donors was 1.1%. Most of the donors were white and males. In the multivariate analysis, independent predictors of anti-HCV positivity were: intravenous drug use, blood transfusion >10 years earlier, having had two to four sexually transmitted diseases, incarceration, tattooing, sex with a hepatitis B or C virus carrier or with intravenous drug users. CONCLUSION: Intravenous drug use, blood transfusion, and tattooing were the main risk factors for anti-HCV positivity among blood donors from southern Brazil, but sexual HCV transmission should also be considered

The stability of money demand in the long-run: Italy 1861–2011

Money demand stability is a crucial issue for monetary policy efficacy, and it is particularly endangered when substantial changes occur in the monetary system. By implementing the ARDL technique, this study intends to estimate the impact of money demand determinants in Italy over a long period (1861–2011) and to investigate the stability of the estimated relations. We show that instability cannot be excluded when a standard money demand function is estimated, irrespectively of the use of M1 or M2. Then, we argue that the reason for possible instability resides in the omission of relevant variables, as we show that a fully stable demand for narrow money (M1) can be obtained from an augmented money demand function involving real exchange rate and its volatility as additional explanatory variables. These results also allow us to argue that narrower monetary aggregates should be employed in order to obtain a stable estimated relation

Role of Zirconium on the structural film evolution and on the optical properties of sol-gel hybrid organic/inorganic glass films

References Citations Metrics Reprints & Permissions Get access Abstract The growing and curing dependence of structural and optical properties of sol-gel Si- and Zr- based films was studied by using the fast Fourier Transform IR (FTIR) spectroscopy in the 500–5000 cm^−1 range. Samples are prepared by means of a spin-coating technique with different ratios between the precursor fraction. The introduction of Zirconium in the starting solution confers both rigidity and high refractive index to the films. The IR spectra are characterized by three main absorption regions: from 700 to 1250 cm^−1 the ZrO and Si-O-Si stretching modes are dominant, from 1250 to 1800 cm−1 the absorption is strongly dependent on the Zr content and the region from 2750 to 3500 cm^−1 is characterized by the CH2 and CH3 vibrational peaks and by the OH broad band. The curing process is monitored after isochronal thermal treatments in the range 50–500°C