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Abstract Objective There is growing evidence supporting the utilization of the radial artery as a secondary arterial graft in coronary artery bypass grafting (CABG) surgery. However, debates continue over the recovery period of the radial artery following angiography. This study aims to evaluate the clinical outcomes and experiences related to the use of the radial artery post-angiography in total arterial coronary revascularization. Methods A retrospective analysis was performed on data from patients who underwent total arterial CABG surgery at the University of Hong Kong Shenzhen Hospital from July 1, 2020, to September 30, 2022. Preoperative assessments included ultrasound evaluations of radial artery blood flow, diameter, intimal integrity, and the Allen test. Additionally, pathological examinations of the distal radial artery and coronary artery CT angiography were conducted, along with postoperative follow-up to assess the safety and efficacy of using the radial artery in patients undergoing total arterial CABG. Results A total of 117 patients, compromising 102 males and 15 females with an average age of 60.0 ± 10.0 years, underwent total arterial CABG. The internal mammary artery was used in situ in 108 cases, while in 4 cases, it was grafted to the ascending aorta due to length limitations. Bilateral radial arteries were utilized in 88 patients, and bilateral internal mammary arteries in 4 patients. Anastomoses of the proximal radial arteries to the proximal ascending aorta included 42 cases using distal T-anastomosis and 4 using sequential grafts. The interval between bypass surgery and coronary angiography ranged from 7 to 14 days. Pathological examination revealed intact intima and continuous elastic membranes with no significant inflammatory infiltration or hyperplastic lumen stenosis in the radial arteries. There were no hospital deaths, 3 cases of perioperative cerebral infarction, 1 secondary thoracotomy for hemorrhage control, 21 instances of intra-aortic balloon pump (IABP) assistance, and 2 cases of poor wound healing that improved following debridement. CT angiography performed 2 weeks post-surgery showed no internal mammary artery occlusions, but 4 radial artery occlusions were noted. Conclusion Ultrasound may be used within 2 weeks post-angiography to assess the recovery of the radial artery in some patients. Radial arteries with intact intima may be considered in conjunction with the internal mammary artery for total arterial coronary CABG. However, long-term outcomes of these grafts require further validation through larger prospective studies.

Non-destructive test methods are usually used for up to 2 months old bored concrete piles. It helps to determine the concrete properties of newly installed pile foundations. This research work represents a unique investigation of 80 bored concrete piles that are tested with different non-destructive methods 34 years from installation. Therefore, the main objective of this article is to provide an analysis of different non-destructive testing (pile integrity test (PIT); P-wave test; ultrasound test (UPV)) results for old concrete piles and to provide suggestions for the prediction of experimental results. Furthermore, the experimental results of different methods are compared with each other. Based on the results of this research and found in the literature, a theoretical method is proposed to predict the relationship between wave velocity and concrete strength for a wider range of concrete strength (5–115 MPa). Furthermore, coefficients are proposed for the prediction of the relationship between the dynamic modulus of elasticity and the strength of the concrete and give significantly higher precision compared to the ones proposed in the literature.

The objective of this study is to evaluate the ultrasound test to estimate the depth of cracks in concrete, using a mathematical model published in the literature, and to verify this depth with more accurate results. Four concrete test specimens were molded for each proposed crack depth (5 cm, 10 cm, and 15 cm), simulated using zinc plates, placed during molding and removed before concrete hardening. The results show that the test is sensitive enough to detect the presence of the cracks in the concrete. The mathematical model used allowed for an estimation of the depths of most cracks, but the results are scattered and have a high margin of error for the depths of 5 cm and 15 cm. The cracks of 10-cm depth produced better results.

Abstract This work aims to reduce the energy consumption and thus increase the availability of blast furnace compressors of a steelmaking company, located in Alto Paraopeba region in Minas Gerais state, Brazil, through the elimination of waste points in the compressed air distribution. In order to develop this work, an ultrasound test in the compressed air line was performed to identify and quantify leaks in the flow. Once the leaks were identified, they were eliminated through corrective maintenance and improvements, and then the energy consumption scenarios before and after the improvements were compared. As a result, the average monthly electricity consumption in the reporting period decreased by 57.2%. In addition, one compressor was set aside in stand-by condition, as in the original plant. Thus, one can prove the efficiency in eliminating of waste points in compressed air distribution, since the reduction of energy consumption is important for the company to remain competitive, as the cost of electric energy affects the final price of the final products.