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Waste-tire textile fibers (WTTF) represent a challenge for the recycling industry since there are currently very few alternatives for their use. In this study, an evaluation of the effect of a new additive developed in two granular formats from WTTF on the fatigue behavior of asphalt mixtures was performed. For the first format of the WTTF-based additive, its effect was evaluated on hot-mix asphalt (HMA), while for the second format of the additive, the effects were evaluated on stone mastic asphalt (SMA). This second format represents an alternative that allows for the total replacement of the cellulose stabilizing additive used in the reference mix. The evaluation of fatigue damage in the mixes was performed using the four-point bending beam (4PB) test specified in European standard EN 12697-24. The test results show that the asphalt mixtures manufactured with WTTF-based additives exhibited a higher capacity to resist load cycles before failure compared to the reference mixtures. Likewise, once the asphalt mixtures were evaluated in a pavement structure by means of an empirical mechanistic analysis, the pavement structures composed of asphalt mixtures with WTTF-based additives showed significant improvements in their durability for the different load axes evaluated. For an average thickness of 15 cm of asphalt mix of a pavement-type structure, the use of the WTTF additive increases the durability of the structures by up to 129% and 112% compared to the HMA and SMA reference mixtures, respectively. These results show that both formats of the WTTF-based admixture improve the fatigue damage resistance of the HMA and SMA asphalt mixtures.
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Purpose: To determine the energy expenditure in phacoemulsification surgery expressed as cumulative dissipated energy (CDE) among the divide and conquer, ultrachopper-assisted divide and conquer, and phaco-chop techniques for dense cataract removal. Patients and Methods: The clinical data were obtained from the medical charts of dense cataracts patients undergoing routine phacoemulsification employing any of three phaco-fragmentation techniques, including divide and conquer using the Kelman 0.9 mm tip, the ultrachopper tip, and the phaco-chop technique using the Kelman 0.9 mm tip. Cumulated dissipated energy (CDE), longitudinal ultrasound time (UST), and endothelial cell loss were compared among groups at the one-month postoperative. Results: Surgeries from 90 eyes were analyzed, among whom the conventional divide-and-conquer technique group included 30 patients, 32 in the ultrachopper group, and 28 in the phaco-chop technique group. The average CDE in the conventional divide and conquer group was 44.52 ± 23.00, the ultrachopper technique was 43.27 ± 23.18, and 20.11 ± 11.06 in the phaco-chop group. Phaco-fragmentation chop demonstrated significantly lower CDE than the other techniques (p= <0.0001). The phaco-chop technique showed statistically significantly lower CDE when compared to the other two groups (p=<0.0001) with 93.96 ± 39.71 seconds. There were no statistically significant differences in postoperative endothelial cell density between groups (p=0.4916). Conclusion: The use of the phaco-chop technique in hard cataract phacoemulsification represents a lower energy expenditure than divide and conquer and ultrachopper techniques; nevertheless, no differences regarding endothelial density loss were evidenced.
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AIM: To compare under similar conditions intraoperative surgical efficiencies metrics between an active fluidics and a gravity based phacoemulsification systems. METHODS: Adult patients who were diagnosed with a cataract that compromised visual acuity inferior to 20/40 were included in the study. Patients were excluded from the study if they had a history of severe retinal disorders, clinically significant corneal endothelial dystrophy or history of corneal disease. All phacoemulsification surgeries were performed by a single surgeon. Both phacoemulsification systems used the 0.9 mm 45-degree aspiration bypass system Intrepid Balanced tip and the 0.9 mm Intrepid Ultra infusion sleeve. All cataracts were classified using the Lens Opacities Classification System III, cumulative dissipated energy (CDE) and aspiration fluids were measured in each surgery. RESULTS: Totally 2000 eyes were included in the study. Phacoemulsification was performed in 1000 (50%) eyes with an active fluid dynamics system and in 1000 (50%) eyes with a gravity-based fluidic system. Mean CDE until fracture of the lens was 1.1 and 1.9 percent-seconds and total mean CDE used was 5.6 and 7.2 percent-seconds using an active fluidics dynamics system and gravity-based fluidic system, respectively (P<0.001). Mean aspiration fluids used were 70 mL using an active fluidics dynamics system and 85 mL using a gravity-based fluidic system (P<0.001). CONCLUSION: This study evidences that surgeries performed under similar conditions (same surgeon, phaco tip and sleeve) with the active fluidics dynamics system required significantly lower CDE and aspiration fluids.
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PURPOSE: To compare the cumulative dissipated energy (CDE), aspiration time and estimated aspiration fluid utilized during phacoemulsification cataract surgery using two phacoemulsification systems . METHODS: A total of 164 consecutive eyes of 164 patients undergoing cataract surgery, 82 in the active-fluidics group and 82 in the gravity-fluidics group were enrolled in this study. Cataracts graded NII to NIII using LOCS II were included. Each subject was randomly assigned to one of the two platforms with a specific configuration: the active-fluidics Centurion ® phacoemulsification system or the gravity-fluidics Infiniti ® Vision System. CDE, aspiration time (AT) and the mean estimated aspiration fluid (EAF) were registered and compared. RESULTS: A mean age of 68.3 ± 9.8 years was found (range 57-92 years), and no significant difference was evident between both groups. A positive correlation between the CDE values obtained by both platforms was verified (r = 0.271, R 2 = 0.073, P = 0.013). Similarly, a significant correlation was evidenced for the EAF (r = 0.334, R 2 = 0.112, P = 0.046) and AT values (r = 0.156, R 2 = 0.024, P = 0.161). A statistically significantly lower CDE count, aspiration time and estimated fluid were obtained using the active-fluidics configuration when compared to the gravity-fluidics configuration by 19.29, 12.10 and 9.29%, respectively (P = 0.001, P < 0.0001 and P = 0.001). CONCLUSIONS: The active-fluidics Centurion ® phacoemulsification system achieved higher surgical efficiency than the gravity-fluidics Infiniti ® IP system for NII and NIII cataracts.