We describe a novel experimental device, the VaMa (Vatavuk and Marić) artificial intraocular lens (IOL) capsule, and a method that enables all IOL types to be implanted in the bag. We present the application of the device and the procedure in patients with aphakia and native capsule damage and without efficient capsular support. The VaMa device and the method facilitate IOL exchange due to refractive errors and, in the case of their invention, the implementation of superior IOLs in the future. The postoperative results after the implantation of the VaMa capsule along with IOLs in three patients are promising, with significant visual improvement and without adverse events 7 to 10 months postoperatively.
Polymer composites have been utilized across various industries, especially in transportation, for many years. With a growing emphasis on sustainable production resources, the industry increasingly favours composite materials reinforced with natural fibres or particles. Unlike conventional fibres such as glass, carbon, or aramid, natural fibres typically have low compatibility with polymer matrices, often necessitating pretreatment to enhance bonding. In this study, coir fibres were physically and chemically treated with sodium bicarbonate solutions at varying concentrations (5–15%) and immersion durations (0–5 days). The treated fibres were then mixed into epoxy resin and poured into moulds to produce test specimens for evaluating mechanical properties. The fibre content in the composites ranged from 10 to 20%. Statistical analysis revealed that immersion time significantly affects all mechanical properties tested (tensile modulus, tensile strength, strain, and impact strength). Solution concentration significantly influences tensile modulus and strain, while fibre content significantly affects tensile modulus and strength. The conducted optimization shows that the best mechanical properties are achieved with the minimum tested coir fibre content of 10%. Maximum stiffness and strength can be expected with the longest immersion time of 5 days in the highest solution concentration of 15%. The best strain and impact strength properties, however, are observed at the lowest solution concentration of 5%.
The paper presents the optimisation of mould for injection moulding as well as injection moulding process parameters using numerical computer simulation in the Moldex3D software package. The optimisation process will be applied to a specific moulded part – branching terminal block – and an already manufactured mould. The paper includes evaluation of the existing mould for injection moulding designed and manufactured without application of numerical simulation of injection moulding process. According to the shortcomings found out in evaluation process, by application of numerical simulation of injection moulding process, the optimisation of the mould design was conducted in several stages to achieve as optimal as possible moulded part quality and injection moulding process parameters without dramatic changes in already manufactured mould.