7,093 research outputs found
Shaking table test for a scale-down reinforced concrete structure considering corrosive deterioration
The degradation of concrete and rebar corrosion are considered a key factor in the durability of reinforced concrete structures and a major concern for civil engineers over the past few years. This study is focus on the variation of natural frequency, dynamic properties and seismic spectral in a deteriorated scale-down reinforced concrete frame specimen with rebar corrosion. The dynamic properties were experimentally studied though shaking table tests and the corrosive behaviors were experimentally studied though accelerated corrosion test. Test results presented that the corroded reinforced concrete specimens presented the changes in the dynamic response especially natural frequencies and response spectrum and rebar corrosion caused significant charges in dynamic responses. In conclusion, the deteriorated scale-down reinforced concrete test is useful for structural assessments and appraisals applied to full-scale structures
Combining radiofrequency ablation and ethanol injection may achieve comparable long-term outcomes in larger hepatocellular carcinoma (3.1–4 cm) and in high-risk locations
AbstractRadiofrequency ablation (RFA) is more effective for hepatocellular carcinoma (HCC) < 3 cm. Combining percutaneous ethanol injection and RFA for HCC can increase ablation; however, the long-term outcome remains unknown. The aim of this study was to compare long-term outcomes between patients with HCC of 2–3 cm versus 3.1–4 cm and in high-risk versus non-high-risk locations after combination therapy. The primary endpoint was overall survival and the secondary endpoint was local tumor progression (LTP). Fifty-four consecutive patients with 72 tumors were enrolled. Twenty-two (30.6%) tumors and 60 (83.3%) tumors were of 3.1–4 cm and in high-risk locations, respectively. Primary technique effectiveness was comparable between HCC of 2–3 cm versus 3.1–4 cm (98% vs. 95.5%, p = 0.521), and HCC in non-high risk and high-risk locations (100% vs. 96.7%, p = 1.000). The cumulative survival rates at 1 year, 3 years, and 5 years were 90.3%, 78.9%, and 60.3%, respectively, in patients with HCC of 2–3 cm; 95.0%, 84.4%, and 69.3% in HCC of 3.1–4.0 cm (p = 0.397); 90.0%, 71.1%, and 71.1% in patients with HCC in non-high-risk locations; and 92.7%, 81.6%, and 65.4% in high-risk locations (p = 0.979). The cumulative LTP rates at 1 year, 3 years, and 5 years were 10.2%, 32.6%, and 32.6%, respectively, in all HCCs; 12.6%, 33.9%, and 33.9% in HCC of 2–3 cm; 4.8%, 29.5%, and 29.5% in HCC of 3.1–4 cm (p = 0.616); 16.7%, 50.0%, and 50.0% in patients with HCC in non-high-risk locations; and 8.8%, 29.9%, and 29.9% in patients with HCC in high-risk locations (p = 0.283). The cumulative survival and LTP rates were not significantly different among the various subgroups. Combining RFA and percutaneous ethanol injection achieved comparable long-term outcomes in HCCs of 2–3 cm versus 3.1–4.0 cm and in high-risk versus non-high-risk locations. A randomized controlled or cohort studies with larger sample size are warranted
Infected Aortic Aneurysms
Infected aortic aneurysms are surgical urgencies, requiring prompt management to avoid the development of catastrophic complications. Although traditional open surgery composed of radical debridement and aortic reconstruction remains the gold-standard, many favorable results of the endovascular repair strategy have been reported. In this chapter, the etiology, bacteriology, clinical manifestation, and diagnostic criteria of infected aortic aneurysms will be discussed in detail at first, followed by a comprehensive review of both traditional open surgery and endovascular repair, based on current evidences and the authors’ institutional experience. Along with long-term oral antibiotic suppression and aggressive adjunctive procedures, endovascular repair for uncomplicated infected aortic aneurysms could be a definite treatment alternative to traditional open surgery in the endovascular era
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