Rapid enlargement of choroidal osteoma in an adult patient

Dear Editor,We present the first adult patient with rapid enlargement of choroidal osteoma.Choroidal osteoma is a rare benign tumor characterized by mature cancellous bone in the choroid[1].The usual progress of the tumor is not rapid.Herein,we report that choroidal osteoma enlarged rapidly in an adult patient with Rosai-Dorfman disease(RDD).This study adhered to the tenets of the Declaration of Helsinki,and the written informed consent was obtained from the patient(YKEC-KT-2022-024-P002).

Bilateral diffuse uveal melanocytic proliferation associated with endometrial carcinoma–multimodal imaging analysis

Dear Editor,We present a rare case of bilateral diffuse uveal melanocytic proliferation (BDUMP) associated with endometrial carcinoma.BDUMP is a rare paraneoplastic ocular syndrome with generally poor prognosis.Typical features include:1) multiple subtle,round,or oval red patches in the retinal pigment epithelium (RPE) of the posterior fundus;2)multifocal areas of early hyperfluorescence corresponding to these patches;3) development of multiple,slightly elevated pigmented and non-pigmented uveal melanocytic tumours with diffuse thickening of the uveal tracts;4) exudative retinal detachment;5) rapid progression of cataracts.These patches progressively increase in size and merge into the giraffe-like pattern characteristic of BDUMP.Additional signs may be present,including cysts in the ciliary body and iris,dilated episcleral vessels,and a shallow anterior chamber.

Interface strengthening for thermal sprayed WC-10Co4Cr coating subjected to pulsed magnetic treatment

The reliability of the coated industry components demands ideal fatigue properties of the coating,and it is mainly determined by the performance of the interfaces.In this study,pulsed magnetic treatment(PMT)was applied to the thermal sprayed WC-10Co4Cr coating,and the fatigue lifetime of the coated bolt increased by 219.82%under an imitation of the operating mode condition.Scratch tests further proved that both the adhesion and cohesion strength were improved after PMT,and they benefit from the interface strengthening effects.The formation of coherent WC/Co interfaces was characterized by in-situ transmission electron microscopy(TEM),and the molecular dynamic simulations indicate that the work of separation of these interfaces is much higher than the original disordered ones.Residual stress was relaxed and distributed more homogeneously after PMT,and it mainly contributes to the coating/substrate strengthening.This work provides a new post-treatment method focusing on the interfaces in the WC-based coating and gives insight into its mechanism so that it is hopeful to be applied to other kinds of coatings.

Oxidation damage and interfacial failure of dissimilar metal welds containing ferritic heat resistant steels

The ex-service steam tubes containing dissimilar metal weld(DMW)between high Cr ferritic steel T91 and austenitic stainless steel TP347H and the ex-service steam tubes containing DMW between low Cr ferritic steel G102 and austenitic stainless steel TP347H were obtained from coal-fired thermal power plants in China,and their microstructures at the nickel-based weld metal(WM)/ferritic steel interfaces and oxidation characteristics were investigated.After operating for 15,000 h at steam temperature of 541 C and steam pressure of 17.5 MPa,a G102/TP347H DMW failed along the WM/G102 steel interface,which was a dangerous premature failure mode without obvious plastic deformation.This interfacial failure was attributed to the interaction between oxidation and cracking along the interface,where fracture appeared to be related with the strain concentration at the interface.Oxide notch along the WM/G102 steel interface was the precursor of premature interfacial failure of DMW involving G102.For the DMW involving high Cr ferritic steel T91,ferritic steel side could form a Cr-rich passive film during service and thus would not be further oxidized after operating for 67,000 h at steam temperature of 541 C and steam pressure of 3.5 MPa.It was concluded that oxidation played a more important role in failure of these DMWs,and retarding the development of oxidation and avoiding the interfacial oxide notch would dramatically improve the service performance of steam tubes containing DMWs.