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Background: Hypoplasia of the transverse sinus (TS) is a common anatomical variation. However, the relationship between TS hypoplasia and venous thrombosis has not been studied. We analyzed the hypothesis that TS hypoplasia is a predisposing factor for ipsilateral thrombosis.Materials and Methods: We retrospectively evaluated 20 confirmed cases with isolated TS thrombosis and 43 age- and sex-matched controls. TS thrombosis and hypoplasia were diagnosed using both computed tomography and magnetic resonance venography. Hypoplasia was defined as a TS diameter less than 50% of the cross-sectional diameter of the lumen of the distal superior sagittal sinus and by a bony groove ratio less than 1.02. Univariate analysis was performed to evaluate the association between TS hypoplasia and thrombosis.Results: There were a total of 45 hypoplastic TS: 31 (49%) left hypoplastic TS (12 (60%) cases vs 19 (44%) controls (P = .24), and 14 (22%) right hypoplastic TS (9 (45%) cases vs 5 (12%) controls (P = .003). TS hypoplasia was more frequently found in cases (n = 18, 90.0%) than in controls (n = 22, 51.2%; relative risk 1.7, confidence interval [CI] 95% 1.3-2.4, P = .003). Hypoplastic TS and ipsilateral TS thrombosis showed a significant association (P = .002 for right and P = .008 for left TS hypoplasia) with relative risk of 3.8 (95% CI 1.3-10) for right and 7.5 (95% CI 1.1-48) for left hypoplasia. No significant association was found between hypoplastic TS and functional outcome at 30- or 90-day follow-up.Conclusion: TS hypoplasia might be a predisposing factor for ipsilateral TS thrombosis, but not for functional outcome. [ABSTRACT FROM AUTHOR]

Objectives: COVID-19 pandemic has forced important changes in health care worldwide. Stroke care networks have been affected, especially during peak periods. We assessed the impact of the pandemic and lockdowns in stroke admissions and care in Latin America.Materials and Methods: A multinational study (7 countries, 18 centers) of patients admitted during the pandemic outbreak (March-June 2020). Comparisons were made with the same period in 2019. Numbers of cases, stroke etiology and severity, acute care and hospitalization outcomes were assessed.Results: Most countries reported mild decreases in stroke admissions compared to the same period of 2019 (1187 vs. 1166, p = 0.03). Among stroke subtypes, there was a reduction in ischemic strokes (IS) admissions (78.3% vs. 73.9%, p = 0.01) compared with 2019, especially in IS with NIHSS 0-5 (50.1% vs. 44.9%, p = 0.03). A substantial increase in the proportion of stroke admissions beyond 48 h from symptoms onset was observed (13.8% vs. 20.5%, p < 0.001). Nevertheless, no differences in total reperfusion treatment rates were observed, with similar door-to-needle, door-to-CT, and door-to-groin times in both periods. Other stroke outcomes, as all-type mortality during hospitalization (4.9% vs. 9.7%, p < 0.001), length of stay (IQR 1-5 days vs. 0-9 days, p < 0.001), and likelihood to be discharged home (91.6% vs. 83.0%, p < 0.001), were compromised during COVID-19 lockdown period.Conclusions: In this Latin America survey, there was a mild decrease in admissions of IS during the COVID-19 lockdown period, with a significant delay in time to consultations and worse hospitalization outcomes. [ABSTRACT FROM AUTHOR]

• RRA treatment has not affected the tensile mechanical properties of 7075-T6. • 7075-T6 and RRA resulted in similar fatigue response. • Nitrided material presented the worst fatigue performance. • Nitriding also resulted in the lowest notch sensitivity. Aluminum alloys are widely used in aircraft components, which present the fatigue process as one of the main failure modes. The aeronautical industry has been searching for alternatives to increase the service life and safety of structural components. To address this issue, this work subjected the 7075-T6 alloy to retrogression and re-aging (RRA) heat treatment and plasma nitriding in order to obtain an improvement in the corrosion resistance. The objective was then to evaluate whether such treatments affected the fatigue behavior. Fatigue tests were carried out on the material with a smooth surface and with a notch (theoretical stress concentration factor of 5.7). A maximum likelihood estimation method was used to estimate the S-N curve parameters. The fatigue behavior without notch for the T6 and RRA treatments was similar, which is expected because the resulting microstructure of the RRA condition is composed of a homogeneous distribution of very fine η' precipitates in the aluminum matrix, similar to the T6 condition. The worst fatigue behavior without notch was found for the material underplasma nitriding for two main reasons: the softening of the microstructure after processing and the substantial increase of the surface roughness. Regarding the notched material, the fatigue performance was reduced to a similar level regardless of the condition. [ABSTRACT FROM AUTHOR]