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Aim To report silicone oil tamponade induced vasculitis in the early post operative period - a rare manifestation of ‘Toxic Posterior Segment Syndrome’ after pars plana vitrectomy for rhegmatogenous retinal detachment.Case description A 50-year-old gentleman presented with vasculitis after a pars plana vitrectomy with silicone oil tamponade on the first post-operative day. He was started on oral steroids (1 mg/ kg) tapered sequentially every week. All signs of vasculitis resolved over a period of one month after which the silicone oil was removed. The patient maintained a visual acuity of 20/90 even after 3 months. There was no recurrence of vasculitis observed thereafter.Conclusion Silicone oil induced vasculitis is a rarely described entity, especially as a manifestation of toxic posterior segment syndrome. This differential must be kept in mind even on the first post-operative day in cases where silicone oil has been used for tamponade.

Introduction Tuberculosis can involve any organ in the body including ocular tissue of which the uveal tissue is most commonly infected. Choroidal involvement ranges from choroidal tubercles to granulomas. This is one of the few cases of a solitary choroidal granuloma with no other systemic symptoms in an immunocompetent child.Method A case report.Results A 12-year-old female, presented with diminution of vision in the left eye for a month. The anterior segment of her left eye was normal. A fundus examination revealed an isolated orangish-yellow choroidal mass, 4 DD in size, involving the posterior pole with overlying subretinal exudation. CT scan of the thorax showed large pulmonary, cervical and pancreatic lymph nodes, along with lytic lesions of the thoracic vertebrae. Excision biopsy of the cervical lymph nodes showed caseating granulomas with no e/o malignancies on histopathology. The patient was started on anti-tubercular therapy. Six months after the treatment, the lesion had reduced in size and her vision had improved.Conclusion Isolated choroidal tuberculomas can be present in eyes with little associated ocular inflammation and no other symptoms of systemic tuberculosis. High suspicion, early diagnosis and rapid initiation of medication are important for the treatment of ocular and systemic tuberculosis.

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Mechanically alloyed Al-5083 powders with different milling times are consolidated by equal channel angular pressing (ECAP) at room temperature (RT), at high temperature (HT), up to two passes in Route A and their mechanical and physical properties are studied in this paper. Microstructural and tensile tests of RT ECAPed samples reveal weaker bonds between the particles which result in poor tensile strength and ductility. Furthermore, the fractograph of RT ECAPed samples shows that the failure is due to particle pull-out as a result of poor metallurgical bonding. Unmilled (0 h) powder is found to have achieved 99.22% of its theoretical density and 45 HRB after the first pass in HT ECAP. However, microstructural studies and tensile tests revealed good metallurgical bonds between the particles. Furthermore, the fractured surface of compacts shows that the failure surface is dominated by the ductile fracture mode. HT ECAP followed by sintering is a suitable method for achieving metallurgical bonding between microparticles.

This study was aimed at developing low-cost composites with high specific strength and better performance by incorporating agro-waste as reinforcements. The stir-casting technique was adopted for fabricating composites with aluminum (Al) 4032 as matrix material and 0, 2, 4 and 6 wt.% rice husk ash (RHA) as reinforcements. The mechanical properties of the produced composites were investigated, and the wear rate under dry conditions was also experimented on, to assess the characteristics of the produced composites. Energy-dispersive X-ray spectroscopy and scanning electron microscopy analyses were done to study the presence and distribution of reinforcements in the matrix material. The surface of specimens after wear test was analyzed from optical microscope images. The influence of process parameters such as reinforcement (wt.%), speed (revolutions per min (rpm)) and load (N) on wear rate was identified, and the parameters were optimized for minimum wear rate using a Taguchi L16orthogonal array. The percentage contribution of process parameters was obtained by performing analysis of variance. Better results were obtained for composites with 6 wt.% RHA with 84 HRB, 92.30 HV, ultimate tensile strength of 383.73 MPa and ultimate compressive strength of 571.6 MPa. Minimum wear rate was obtained for composites with 6 wt.% RHA at 100 rpm and 10 N. Speed was found to be the most contributing factor, with 72.94%, followed by load, with 13.34%, and weight percentage of reinforcements, with 11.88%.

Image formation over long horizontal or slant paths is of interest in surveillance and remote sensing. Image reconstructions of isolated objects are presented using active illumination in long-path, strong-turbulence conditions using a wave-optics simulation to produce the images. Fast-running reconstruction algorithms are used, including a novel single-frame blind iterative deconvolution algorithm and a generalized expectation maximization algorithm. Significant improvements in image quality and image recognizability can be found for spherical-wave Rytov variances up to 0.4 and for up to 10 atmospheric coherence lengths across the aperture in uniform-turbulence scenarios over a 30 km range. For these conditions, the isoplanatic patch angle is comparable to the diffraction angle, and there are 20 or more isoplanatic patches across the objects considered. The results are compared with idealized atmospheric phase correction with an incoherent beacon. Several image quality metrics are considered. Results for strongest turbulence are explained in terms of a local average of the point spread function and the central limit theorem for cases in which there are many isoplanatic patches across the object.

Titanium is a hard metal with good mechanical properties, corrosion resistant and biocompatibility which makes it have a wide range of applications (biomedical and aerospace). Severe plastic deformation (SPD) is employed to produce Ultrafine Grained (UFG) structures. UFG structures have better mechanical properties due to their compaction. Equal Channel Angular Pressing (ECAP) is adapted to produce a UFG structure in Titanium. In this process, titanium sponge powder is filled in the aluminium shell by intermediate tapping to fill the volume of the shell. The shell is then closed with an Al cap and ECAP is done with continuous back pressure at 300°C. The test specimen has undergone four passes in route BC at different back pressure (50, 100 and 150 MPa) where titanium is consolidated without any crack. Titanium showed decreased grain size and porosity with increasing backpressure. In particular, it is seen that the sample ECAPed by 100 MPa backpressure showed a relative density of about 98% with a hardness of 37 HRC. It is seen that ECAP is more economical and the product obtained by the ECAP process has better properties.

The goal of this research work is to study the role of equal channel angular pressing on consolidation behavior of machined chips of CP Al through ECAP. The chips are collected by orthogonal cutting with cutting edge angle 75° and depth of cut 0.2 mm. The ECAP die with Φ = 90° (channel angle) and Ψ = 20° (corner angle) is used for consolidation of machined chips. The consolidation is done by pre-heating the chips at 200°C upto four passes through processing route BC. The maximum density of 99% and hardness of 94 HV was obtained after 4 ECAP passes. Tribological properties is evaluated by Pin-on-disc dry wear testing for three different loads at a constant sliding speed 750 RPM and distance of 5 kms. Chip consolidated CP Al is inferior in wear resistance with as-received CP Al owed to localised debonding of chips with the sliding disc.

Public transport is designed to move people efficiently and affordably around their communities. Millions of people internationally with disabilities rely on public transport every day to connect them to services, work, educational and social events. Many of these people attempt to board public transport using a powered mobility aid (such as an electric wheelchair, mobility scooter, or gopher) and this number is expected to rise as the population ages. Evidence suggests that many people have difficulty getting their powered mobility aids on and off public transport vehicles, and consumers, vendors and the health care-professionals involved in recommending mobility aids have no way of knowing which powered mobility aids are compatible with existing public transport configurations. The purpose of this paper is to demonstrate how existing 3D technologies and software can be applied to solve this real world problem using the example of buses. This proof-of-principle paper describes the process of scanning buses and powered mobility aids in 3D, together with descriptions of the prototype software to undertake the computerised process, to determine the compatibility of powered mobility aids for access on buses. Feasibility is then demonstrated using an example of one bus and one powered mobility aid. This paper is of interest to researchers wishing to examine the application of 3D technologies, health care providers and consumers who select powered mobility aids, as well as transport policy makers and conveyance commissioners who can access 3D data to optimise transport network accessibility for all community members.