Objectives: Sleep disorders in patients on hemodialysis are frequent, but few studies correlate these disorders with autonomic dysfunction in these patients. This study aimed to verify whether clinical and laboratory variables and heart rate variability are associated with worse sleep quality verified by the Pittsburg subjective scale in patients on hemodialysis. Material and Methods: A cross-sectional study was performed on forty-eight patients. Epidemiological, clinical, and laboratory data were collected. After were performed by recording the heart rate variability and applied Pittsburg questionnaires, Beck anxiety index (BAI), and Beck depression index (BDI). The global PSQI score >5 indicates that a person is a poor sleeper, the patients were divided according to the scores in the Pittsburg questionnaire into good and poor sleepers and the differences between all variables were analyzed. Results: Forty-eight patients were evaluated and the prevalence of 68.7% (n=33) of poor sleep quality was verified. From the depression and anxiety questionnaires, it was found that only 18.7% (n=9) had criteria for depression. In the analysis of the sympathetic dysfunction parameters, it was found that in the group with good sleep quality in the frequency domain (HFm 2 ) and the LFnu in the group with worse sleep quality. There was a positive correlation between sleep quality scores the anxiety and depression scores. It is also verified that the variables LFnu had a positive correlation with higher scores of quality of sleep and HFnu had a negative correlation with the highest scores of quality of sleep. Conclusion: In patients undergoing hemodialysis, the poorest quality of sleep is correlated with worse cardiac autonomic modulation as well as higher scores on the depression and anxiety scales.

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Diante da constante evolução dos ataques de negação de serviço distribuído (DDoS), torna-se necessário o desenvolvimento de técnicas de predição para confrontar essas ameaças. A dissimulação dos ataques e o alto volume de tráfego de rede dificultam o seu reconhecimento. Portanto é importante identificar a preparação dos ataques para aumentar o tempo hábil de combatê-los. Este artigo apresenta um sistema autoadaptativo para a predição dos ataques DDoS. O sistema define automaticamente a melhor configuração da rede neural para distinguir a preparação do ataque DDoS do tráfego normal. Os resultados indicam que o sistema consegue predizer um ataque DDoS em 29 minutos antes do seu início com acurácia superior à literatura (97,89%).

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Background: Cardiovascular diseases are a major cause of morbidity and mortality in Brazil and worldwide. Stratification of the risk of these diseases in asymptomatic patients using biomarkers can lead to early detection of patients at high risk of cardiovascular disease and promote the prevention of relevant events. The intrarenal resistivity index (IRI) is an imaging test that assesses renal perfusion, systemic hemodynamics, and atherosclerosis. It has been reported that changes in IRI are associated with morbidity and mortality in a population of patients with hypertension, diabetes, and chronic kidney disease. The present study tested a hypothesis that IRI is associated with imaging biomarkers of cardiovascular risk in a population of Afro-descendants. Methods: A total of 313 Afro-descendants with high cardiovascular risk were assessed using kidney ultrasound, Doppler echocardiography, carotid Doppler, and computed tomography to assess the calcium score. The individuals were divided into Group 1 with normal IRI and Group 2 with high IRI. Results: The mean intrarenal resistivity index was 0.61 in group 1 and 0.71 in group 2, and the mean age was 56.9 years, with 53% being female. Group 2 had significantly greater left ventricular mass, larger left atrium, and a higher prevalence of diastolic dysfunction (34.5% vs. 66.7%, p<0.0001). Group 2 also had a significantly higher frequency of carotid plaque (31% vs. 64%, p<0.001) as well as total coronary artery calcium score and higher frequency of high coronary artery calcium score (56.37 vs. 212.03, p<0.0001 and 24% vs. 50%, p<0.001, respectively). The presence of diastolic dysfunction with high left atrial pressure, coronary artery calcium score >0, and carotid plaque was independently associated with the intrarenal resistivity index. Conclusions: The intrarenal resistivity index is associated with imaging biomarkers of cardiovascular risk, mainly with the coronary artery calcium score, diastolic dysfunction, and atherosclerotic carotid plaque in people of African descent, with high cardiovascular risk.