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Landslides are a rare but hazardous geological phenomenon in Egypt, with the El Mokattam plateau situated in the eastern part of Cairo covering approximately 64 km 2 and ranging in elevation from 50 to 205 m. This study aims to identify and monitor landslides in the area using various geophysical methods. Twelve Electrical resistivity tomography (ERT) profiles,twenty-two P-wave Seismic Refraction profiles, twenty-two Refraction microtremors profiles, three ground penetrating radar (GPR) profiles and borehole data were utilized to analyze the occurrence of landslides in the El Mokattam Plateau. Additionally, we employed a relatively new geophysical method, studying high-frequency microtremor sounds emitted from landslide collapses at 22 stations. Our analysis identified steep slopes, jointed or fractured rocks, and irrigation water as primary factors contributing to landslides, with irrigation water acting as a lubricant for clays and promoting ground sliding. Examination of high-frequency microtremor sounds revealed a potential correlation between vertical high-frequency spectra at 100 Hz and landslide collapses, which aids in the identification of landslide-prone zones. Therefore, we conclude that seismological studies, particularly spectral analysis of high-frequency and low-amplitude sounds (microtremors) emitted from soil, offer a promising approach for investigating landslides., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Evaluation of mechanical prosthetic valve function is based on echocardiography, but adequate assessment of leaflet motion is limited by acoustic shadowing. Cinefluoroscopy is a standard method to assess leaflet motion, while computed tomography (CT) has been suggested as an alternative. We sought to compare the feasibility of leaflet motion assessment by cinefluoroscopy vs. CT. In 35 prospectively enrolled patients, leaflet motion was assessed in 43 bileaflet mechanical prostheses (29 mitral and 14 aortic) by cinefluoroscopy and non-contrast CT. Assessment was considered feasible when the 'in profile' projection (with the radiographic beam parallel to both the valve ring plane and the tilting axis of discs) could be achieved. Overall feasibility of fluoroscopic assessment was 74% (mitral, 66% vs. aortic, 93%; p = 0.071), while feasibility of CT assessment was 100% (p = 0.003). Among prostheses with unfeasible fluoroscopic assessment, CT suggested an extreme C-arm angulation to achieve the "in profile" projection (RAO: 76.0 ± 5.8°, LAO: 122.7 ± 32.5°, CRA: 51.4 ± 16.0°, CAU: 57.0 ± 18.2°). Among prostheses with feasible assessment by both techniques, fluoroscopy and CT yielded similar opening and closing angles (intraclass correlation coefficient, 0.959-0.998) with lower irradiation with CT as compared with fluoroscopy (26.2[21.1-29.3] vs. 289[179-358] mGy, p < 0.001). While CT scan took 8.7 ± 0.5 s, fluoroscopy required 2.64 ± 1.56 min to achieve and record the "in profile" projection. Non-contrast CT provides a higher feasibility and a quicker evaluation of mechanical prosthetic valve leaflet motion with less irradiation than fluoroscopy, especially in mitral valve position., (© 2022. Springer Japan KK, part of Springer Nature.)

Purpose: High-resolution pulse oximetry (HRPO) may offer a low-cost and simple screening option for sleep-disordered breathing (SDB) that could be vitally important in rural areas with limited healthcare resources and specialty care. Our team hypothesized that application of this technology to a broad cohort of rural dwelling hospitalized individuals would demonstrate congruence similar to previous urban studies comparing HRPO to portable sleep monitors., Methods: This retrospective study was conducted at West Virginia University Hospital and compared indices obtained from HRPO with those obtained from a type III portable sleep monitor (PM) on the same night., Results: A total of 365 individuals underwent evaluation. The mean oxygen desaturation index (18.8 ± 19.3 events/h) from the HRPO was slightly higher than the mean respiratory event index (16.0 ± 18.1 events/h, p ≤ 0.001) from the PM. ROC curves were developed for thresholds of apnea severity predicted by the screening program. The AUC values for all three thresholds exceeded 0.92 and for a respiratory event index (REI) of ≥ 30 was 0.965. Indices from the PM and HRPO demonstrated agreement in those individuals with screening suggestive of moderate to severe disease., Conclusion: This study demonstrates that use of HRPO in screening for SDB in hospitalized patients from rural communities is as accurate as PM and may serve as a simple cost-effective tool to address sleep health disparities in these regions with significant health inequity. Our data extend previous findings by applying HRPO to a larger hospitalized cohort with highly prevalent cardiopulmonary disease., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)