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PURPOSE Head and neck squamous cell carcinoma (HNSCC) incidence is high in South America, where recent data on survival are sparse. We investigated the main predictors of HNSCC survival in Brazil, Argentina, Uruguay, and Colombia. METHODS Sociodemographic and lifestyle information was obtained from standardized interviews, and clinicopathologic data were extracted from medical records and pathologic reports. The Kaplan-Meier method and Cox regression were used for statistical analyses. RESULTS Of 1,463 patients, 378 had a larynx cancer (LC), 78 hypopharynx cancer (HC), 599 oral cavity cancer (OC), and 408 oropharynx cancer (OPC). Most patients (55.5%) were diagnosed with stage IV disease, ranging from 47.6% for LC to 70.8% for OPC. Three-year survival rates were 56.0% for LC, 54.7% for OC, 48.0% for OPC, and 37.8% for HC. In multivariable models, patients with stage IV disease had approximately 7.6 (LC/HC), 11.7 (OC), and 3.5 (OPC) times higher mortality than patients with stage I disease. Current and former drinkers with LC or HC had approximately 2 times higher mortality than never-drinkers. In addition, older age at diagnosis was independently associated with worse survival for all sites. In a subset analysis of 198 patients with OPC with available human papillomavirus (HPV) type 16 data, those with HPV-unrelated OPC had a significantly worse 3-year survival compared with those with HPV-related OPC (44.6% v 75.6%, respectively), corresponding to a 3.4 times higher mortality. CONCLUSION Late stage at diagnosis was the strongest predictor of lower HNSCC survival. Early cancer detection and reduction of harmful alcohol use are fundamental to decrease the high burden of HNSCC in South America.

O presente estudo tem como objetivo a identificação de eventos climáticos na cidade de Bagé/RS a partir de registros de precipitação pluvial no período 1970 a 2016. Nesse intuito, foi efetuada uma análise espectral da distribuição tempo-frequência da série. Tal análise ajusta a resolução do espectrograma por estimativas local da curtose generalizada por estatística de alta ordem- high-order statistics ( HOS ). Objetivando melhor caracterizar os trechos onde as incertezas são mais relevantes, cálculos do grau de entropia foram avaliados. Os resultados são apresentados via densidade espectral de potência do sinal, espectrograma e perfil de curtose relativos aos registros da série pluvial, mostrando-se eficientes no reconhecimento dos padrões climáticos avaliados. Além disso, especificações sobre a mudança no regime de chuvas foram observadas, identificando períodos mais secos no clima da região na década de 80.

This study investigates the effectiveness of a time-frequency analysis of photovoltaic signals with transients caused by shading on the solar panel. The prototype experiment for the signals acquisition was performed by simulating the desired disturbances on the photovoltaic panel. In this direction, the signals were analyzed by a scheme called variable short-time Fourier transform, that has a varying window size over time that is adjusted by local kurtosis given by the fourth normalized cumulant. Thus, a large window size is applied in regions where the kurtosis is relatively high, improving the resolution of time-frequency image. The technique was used on a synthetic signal and current-voltage photovoltaic signals. The results showed that the variable short-time Fourier transform was able to identify transients and classify them over time.