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A new chemical treatment method to extract rich cellulosic fibers from date palm agro-residues is developed. The method yielded high-performance natural date palm fibers based on multistep process, which is efficient, sustainable, and unique. The proposed method consists of three steps: dewaxing, acetylation, and mercerization, which are unique in terms of time control and their sequence resulting in optimal properties of extracted fiber. Each step is strictly time-controlled and designed to achieve specific objectives in preparation for the next step. Optimization techniques including design of experiment are used to adjust input parameters so as to obtain optimized output from the treatment method. Two approaches are used for supplying heat during the fiber extraction procedure i.e. conventional heat source and microwave heat source. Experimental characterization of extracted fibers is carried out to determine its mechanical and physical properties. Results showed 32% increase in crystallinity degree of the treated fiber over the untreated one. The new method achieved around five-fold increase in ultimate tensile strength and three-fold increase in elastic modulus. The significant enhancement in properties of treated fibers over untreated counterparts confirms the effectiveness of the new process. [ABSTRACT FROM AUTHOR]

Introduction Low-cost intraocular lenses (IOLs) have been used in developing countries for many years. In a recent randomized trial, they were found comparable to high-end IOLs in terms of safety, visual outcomes, and posterior capsule opacification (PCO) formation. Our team observed occasional significant refractive changes following Nd:YAG capsulotomy for patients implanted with these IOLs. We aimed to assess the changes in refraction and the anterior chamber (AC) depth induced by Nd:YAG capsulotomy for PCO following implantation of a low-cost IOL. Patients and methods This prospective study was conducted on a cohort of sequential patients with PCO following uncomplicated phacoemulsification and implant of in-the-bag low-cost IOL. Changes in refraction (spherical equivalence, cylinder power, and cylinder axis) were assessed by means of subjective verification of autorefraction. Changes in AC depth were assessed by means of ultrasound biomicroscopy. Changes in cylinder power and axis were included to assess IOL tilt. Results A total of 50 consecutive eyes were enrolled. However, five eyes of three patients were lost to follow-up. A total of 45 eyes of 36 patients completed the pre-YAG and post-YAG assessments. An overall 66.7% of patients were female. An overall 25% had bilateral capsulotomy. The mean age at capsulotomy was 62.4±7.46 years. The mean duration since cataract extraction was 13.3±17.15 months. The mean IOL power was 20.4±2.43 D. No significant changes were found in spherical equivalence, axis of cylinder, and AC depth. However, a significant change in the cylinder power (mean change: 0.36±0.93 D, P=0.039) was observed. Conclusion Our study adds further confirmation on low-cost IOLs being a suitable alternative to high-end IOLs in developing countries and in outreach settings. [ABSTRACT FROM AUTHOR]