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Vat Photopolymerization (VP) is a 3D printing process to fabricate delicate and precise ceramic parts. LCD VP is one of the most economical 3D printing processes and is less explored for ceramic materials. This work investigated the feasibility of consolidating alumina slurry (45 vol %) using an LCD-based resin 3D printer. Results show that a lower exposure time is better for building a multilayer part than a higher exposure time to avoid scattering and delamination. However, higher exposure time is required to bond the initial layers with the build platform. Fine features, such as holes lesser than 3 mm, were not possible to print due to the scattering of the light. A heating rate of 0.1 °C/min is preferable for crack-free debinding. The final sintered part showed sintering shrinkage of 25% in the x-y direction and 30% in the z-direction with a sintered density of 94%.

Abstract We aimed to evaluate the efficacy and safety of low-dose atropine compared to placebo in the Indian population and also to study the impact of various modifiable and non-modifiable factors on myopia progression (MP) and drug efficacy (DE). It was a single-centre prospective placebo-controlled interventional study. 43 participants aged 6–16 years with progressive myopia received 0.01% atropine in the right eyes (treatment) and placebo in the left eyes (control) for 1-year. The main outcome measures were annual MP and axial length elongation (ALE) in treatment and control eyes and their percentage difference between two eyes (drug efficacy). Secondary outcome measures were the occurrence of any adverse events and the correlation of MP, ALE, and DE with various factors. 40 participants (80 eyes) completed the follow-up. After 1-year, MP was 0.25 D (IQR 0.13–0.44) and 0.69 D (IQR 0.50–1.0) (p

Metal inert gas (MIG), Tungsten INERT GAs (TIG), laser and Electron beam (EB) cladding processes are used in cladding-based Additive manufacturing (AM). Only in the case of MIG, the raw-stock is fed axially into the molten pool resulting in the omni-directional cladding. In other processes, the raw-stock is fed off-axially into the molten pool resulting in deviation in the bead geometry from its actual trajectory and varying bead cross-section along the path. As the trajectories vary widely in cladding-based AM, it is required to maintain a consistent raw-stock feeding condition (namely, front, back or sides). Therefore, an auxiliary wire orienting mechanism has been developed which can be easily retrofitted with a conventional TIG cladding torch and CNC machine. The wire orientation angle is computed on-the-fly and hence the NC programme need not provide this information. Although this implementation was demonstrated for TIG, the same methodology holds good for laser and EB too.