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The manufacture of components that have specific material properties in subcomponent regions is highly desired in many sectors. However, it is challenging to achieve via conventional ingot-wrought and joining processing routes. Recently, diffusion bonding titanium alloy powder using field assisted sintering technology (FAST) has demonstrated that multi-material billets can be manufactured. Such billets still need to be machined into final net shaped components. The machinability and machining strategy of such components needs to be better understood if manufacturing of multi-material components is to be economically viable. This is the first study where drilling machinability of FAST diffusion bonded titanium alloys has been investigated. Location indexed force and torque feedback in-process fingerprinting is utilised during the drilling of multi-material titanium alloy billets. The in-process fingerprinting enabled rapid identification of the types and layering order of alloys within the FAST billets. In addition to force feedback, the hardness, hole surface topography and subsurface microstructure were characterised. Although hardness was found to contribute to variation in bond to bond machinability, results highlighted how alloy chemistry and bond composition are intrinsic to the machining directionality and significantly influence the machined surface quality and process stability. The work demonstrates that machining strategy of multi-material drilling needs to be tailored with respect to direction and diffusion bonded alloy pairing to avoid undesirable surface and subsurface damage at bond locations.

Anogenital warts caused by human papillomavirus are common in sexual and gender minorities (SGM). The prevalence of, and factors associated with warts were described for SGM with a high burden of HIV in Nigeria. Individuals who reported anal sex with men were enrolled in the TRUST/RV368 cohort. Participants completed an interviewer-led survey, provided biological samples, and had a physical examination. Specific to the Lagos site, clinic staff offered standardized warts treatment services. RDS-weighted multivariable logistic regression was used to estimate the adjusted odds ratios (AORs) and 95% confidence intervals (CIs) for factors potentially associated with anogenital warts. Of 672 enrolled SGM, 478 (71%) engaged in warts services and had complete data. The median age (interquartile range) was 22 (20-26) years, 272 (52%) initiated sex before age 18, and 347 (79%) were cisgender men. Multiple male sexual partners in the previous year were reported by 448 (90%) of the participants, and 342 (66%) were living with HIV. Warts were diagnosed in 252 (54%), including anal warts in 234 (43%) and penile warts in 44 (8%); 26 (5%) had both anal and penile warts. Factors independently associated with warts included HIV (AOR:2.97; CI:1.44-6.14), engaging in receptive anal sex (AOR:3.49; CI:1.25-9.75), having multiple male sexual partners (AOR:7.26; CI:2.11-24.87), age at sexual debut (AOR:0.53; CI:0.28-0.98), and non-binary gender identity (AOR:0.20; CI:0.05-0.71). Warts were common among SGM in Nigeria, particularly those living with HIV. Administration of HPV vaccination before sexual debut or as a catch-up vaccination may prevent HPV-associated complications., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)