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Introduction: Adolescent girls and young women (AGYW) who may benefit from HIV pre-exposure prophylaxis (PrEP) face high levels of common mental disorders (e.g. depression, anxiety). Common mental disorders can reduce PrEP adherence and increase HIV risk, yet mental health interventions have not been well-integrated into PrEP delivery., Methods: We conducted a four-phase human-centred design process, from December 2020 to April 2022, to understand mental health challenges among AGYW in Johannesburg, South Africa and barriers to integrated mental health and PrEP services. In the "Discover" phase, we conducted in-depth interviews with AGYW and key informants (KIs) in Johannesburg. We conducted a rapid qualitative analysis, informed by the Consolidated Framework for Implementation Research (CFIR), to identify facilitators and barriers of integrated mental health and PrEP services and mapped barriers to potential implementation strategies. In the "Design" and "Build" phases, we conducted stakeholder workshops to iteratively adapt an evidence-based mental health intervention, the Friendship Bench, and refine implementation strategies for South African PrEP delivery settings. In the "Test" phase, we piloted our adapted Friendship Bench package., Results: Interviews with 70 Discover phase participants (48 AGYW, 22 KIs) revealed the importance of integrated mental health and PrEP services for South African AGYW. Interviewees described barriers and implementation strategies for mental health and PrEP services around the CFIR domains: intervention characteristics (e.g. challenges with AGYW "opening up"); outer Johannesburg setting (e.g. community stigma); inner clinic setting (e.g. judgemental healthcare providers); characteristics of counsellors (e.g. training gaps); and the implementation process (e.g. need for demand creation). The Design and Build workshops included 13 AGYW and 15 KIs. Implementation barriers related to the quality and accessibility of public-sector clinic services, lay counsellor training, and community education and demand creation activities were prioritized. This led to 12 key Friendship Bench adaptations and the specification of 10 implementation strategies that were acceptable and feasible in initial pilot testing with three AGYW., Conclusions: Using a human-centred approach, we identified determinants and potential solutions for integrating mental health interventions within PrEP services for South African AGYW. This design process centred stakeholders' perspectives, enabling rapid development of an adapted Friendship Bench intervention implementation package., (© 2024 The Author(s). Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of International AIDS Society.)

This study presents the phase analysis, microstructural characteristics, and mechanical property evaluation of the as-cast and quenched Ti-15Mo-xFe alloys with high iron content ranging from 4 to 12 weight percent. All the four alloys were produced in a vacuum-arc melting furnace. Heat treatment in the form of solution treatment was performed in a muffle furnace at a temperature of 1100 °C, with 1-h holding time and the samples were rapidly quenched in ice-brine. X-ray diffractometer (XRD) was used to analyses the phases present in each alloy whereas the optical microscope (OM) was employed to track the microstructural evolution and percentage porosity. The mechanical properties of the alloys were evaluated using a tensile test and compression test method while the micro-Vickers hardness measurements were conducted to evaluate hardness of the alloys. The XRD patterns of as-cast showed peaks belonging to the β and α″ phases and intermetallic B2 TiFe phases. The as quenched XRD peaks illustrated β phase only and Fe·Ti·O 2 phases. The as-cast OM micrographs revealed equiaxed β grains, substructures, dendritic structure, and pores forming around the grain boundaries. The quenched OM showed only β equiaxed grains with pores throughout the grain boundaries. The tensile properties such as ultimate tensile strength (UTS) and elastic modulus (E) of as-cast TMF0 were 264 MPa and 79 GPa respectively and these properties changed upon quenching to 411 MPa and 66 GPa respectively. The elastic modulus of TMF1 in as-cast condition was 74 GPa. The UTS and E of TMF1, TMF2, and TMF3 in as-cast and quenched conditions were not recorded due to the fragility of the samples that failed prior to yielding any useful data. The compressive strength in as-cast and in quenched condition decreased with an increase in Fe content. The micro-Vickers hardness in as-cast and quenched conditions showed a similar trend with hardness increasing slightly upon quenching for TMF0, TMF1, and TMF3 alloys but slightly decreased in the case of TMF2. The fracture surfaces of all the as-cast and quenched alloys were comprised of ductile and brittle fracture., (© 2024. The Author(s).)

MnPt's exceptional stability and extremely high Néel temperature have generated a lot of interest in data storage applications. Previously, it was reported experimentally that the MnPt alloy shows ferromagnetic (FM) behavior at room temperature. In this study, the effects of partial substitution of Pt with Pd, Au, and Ag on magnetic properties is investigated using density functional theory. The stability of Mn 50 Pt 50-x M x (M = Pd, Au, Ag, x = 6.25, 12.5, 18.75) alloys was assessed by determining their thermodynamic, magnetic, and mechanical properties. The calculated lattice constants of Mn 50 Pt 50 agree well with available theoretical results. The Mn 50 Pt 50-x M x alloys' formability was assessed by measuring the thermodynamic stability using the heat of formation. It was found that B2 Mn 50 Pt 50-x Pd x alloys (0 ≤ x ≤ 18.75) are thermodynamically stable due to the negative heat of formation close to that of a pristine MnPt alloy. Based on the elasticity results, the B2 Mn 50 Pt 50-x Pd x is most likely to undergo martensitic transformation for the entire considered composition range. From the calculated values of the Poisson's ratio, it is shown that an increase in Pd, Ag, and Au effectively improves the ductility of the B2 Mn 50 Pt 50-x M x compounds. It was revealed that ferromagnetism is maintained with Pd addition but significantly reduced in the case of Au and Ag. Thus, this work showed that density functional theory can be exploited to propose new possible compositions for future magnets in spintronic applications.

This work reported the first-principles calculations for the compositional dependence of the energetic, electronic, and magnetic properties of the bimetallic Fe-Pt alloys at ambient conditions. These hybrid alloys have gained substantial attention for their potential industrial applications, due to their outstanding magnetic and structural properties. They possess high magnetocrystalline anisotropy, density, and coercivity. Four Fe-Pt alloys, distinguished by compositions and space groups, were considered in this study, namely P4/mmm-FePt, I4/mmm-Fe 3 Pt, Pm-3m-Fe 3 Pt, and Pm-3m-FePt 3 . The calculated heats of formation energies were negative for all Fe-Pt alloys, demonstrating their stability and experimentally higher formation probability. The P4/mmm-FePt alloy had the lowest magnetic moment, leading to durable magnetic hardness, which made this alloy the most suitable for permanent efficient magnets, and magnetic recording media applications. Moreover, it possessed a relatively large magnetocrystalline anisotropy energy value of 2.966 meV between the in-plane [100] and easy axis [001], suggesting an inside the plane isotropy.

Surface-enhanced Raman spectroscopy (SERS), a marvel that uses surfaces to enhance conventional Raman signals, is proposed for a myriad of applications, such as diagnosis of diseases, pollutants, and many more. The substrates determine the SERS enhancement, and plasmonic metallic nanoparticles such as Au, Ag, and Cu have dominated the field. However, the last decades have failed to translate SERS prototypes into real-life applications. Irreproducibility on the SERS signal that stems from the roughened SERS substrates is the main causative factor for this observation. To mitigate irreproducibility several two-dimensional (2-D) substrates have been sought for use as possible alternatives. Application of 2-D graphene substrates in Raman renders graphene-enhanced Raman spectroscopy (GERS). This account used density functional theory (DFT) substantiated with experimental Raman to compare the enhancement capabilities of plasmonic Au nanoparticles (SERS), graphene substrate (GERS), and coupling of the two SERS and GERS substrates. The DFT also enabled the study of the SERS and GERS systems molecular orbital to gain insight into their mechanisms. The amalgamation of the SERS and GERS occurrence, i.e., graphene doped with plasmonic metallic substrates showed a pronounced enhancement and matched the Au-driven enhancement emanating from both electromagnetic and charge transfer SERS and GERS mechanisms., Competing Interests: Authors NM, TN, HC and LS were employed by Mintek, South Africa. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Mhlanga, Ntho, Chauke and Sikhwivhilu.)