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The recent rise of 2D materials has extended the opportunities of tuning a variety of properties. Tribo-corrosion, the complex synergy between mechanical wear and chemical corrosion, poses significant challenges across numerous industries where materials are subjected to both tribological stressing and corrosive environments. This intricate interplay often leads to accelerated material degradation and failure. This review critically assesses the current state of utilizing 2D nanomaterials to enhance tribo-corrosion and -oxidation behavior. The paper summarizes the fundamental knowledge about tribo-corrosion and -oxidation mechanisms before assessing the key contributions of 2D materials, including graphene, transition metal chalcogenides, hexagonal boron nitride, MXenes, and black phosphorous, regarding the resulting friction and wear behavior. The protective roles of these nanomaterials against corrosion and oxidation are investigated, highlighting their potential in mitigating material degradation. Furthermore, we delve into the nuanced interplay between mechanical and corrosive factors in the specific application of 2D materials for tribo-corrosion and -oxidation protection. The synthesis of key findings underscores the advancements achieved through integrating 2D nanomaterials. An outlook for future research directions is provided, identifying unexplored avenues, and proposing strategies to propel the field forward. This analysis aims at guiding future investigations and developments at the dynamic intersection of 2D nanomaterials, tribo-corrosion, and -oxidation protection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Prior research in sub-Saharan Africa reports dyslipidemia in perinatally human immunodeficiency virus (HIV)-infected children receiving ritonavir-boosted lopinavir (LPV/r) compared with efavirenz; however, interpretation of findings is limited by lack of comparison data from HIV-uninfected children., Methods: We conducted a cross-sectional analysis of lipid profiles and growth within a larger longitudinal cohort study of perinatally HIV-infected and HIV-uninfected children aged 4-9 years in Johannesburg, South Africa. At enrollment, anthropometrics, viral load, CD4, total cholesterol (TC), high-density lipoprotein, low-density lipoprotein (LDL), and triglycerides were measured. Weight-for-age Z-score (WAZ), height-for-age Z-score (HAZ), and body mass index-for-age Z-score (BAZ) were calculated. United States pediatric thresholds for dyslipidemia were used., Results: Five hundred fifty-three HIV-infected and 300 HIV-uninfected children (median age 6.9 years) of similar demographic characteristics were enrolled. Of the HIV-infected children, 94.8% were on combination antiretroviral therapy (cART) (65.4% on LPV/r- and 28.6% on efavirenz-based regimens). Among the treated, 94.3% had a viral load <200 copies/mL. Median CD4% was 34.4. The HIV-infected children had lower mean WAZ (-0.7 vs -0.3, P < .01) and HAZ (-1.1 vs -0.7, P < .01) compared with HIV-uninfected children. A lower proportion of HIV-infected children were overweight (BAZ >1) compared with HIV-uninfected children (14.4% vs 21.7%, P = .04). Whether on LPV/r or efavirenz, a higher proportion of HIV-infected children had borderline/elevated TC or abnormal triglycerides than HIV-uninfected children, although a higher proportion of those on LPV/r had borderline/elevated TC, borderline/elevated LDL, or abnormal triglycerides than those on efavirenz., Conclusions: In a South African cohort of HIV-infected children and population-appropriate HIV-uninfected children, unfavorable alterations in lipid profiles were detected in HIV-infected children regardless of treatment regimen compared with HIV-uninfected children. The HIV-infected children were of smaller size than HIV-uninfected children, but there was a high prevalence of overweight in both groups. Strategies for optimizing growth and early life management of lipid alterations may be warranted.

The purpose of this clinical note is to describe the performance of the Lunar Achilles Insight device in assessing bone quality at the calcaneus in 142 children between the ages of 5 and 11 y accessing healthcare in Johannesburg, South Africa. We observed an asymmetric bimodal distribution in speed of sound (SOS). The minor mode consisted of unusually high SOS values (≥1625 m/s), which were primarily observed among children with foot size <19 cm and height <119 cm. Cortical regions of the bone may have been inadvertently included in the region of interest for smaller feet, causing unusually high SOS values. The unusually high SOS values indicate that the validity of SOS in this device, as it is currently used for measuring bone quality in young children, is questionable. Future studies using this device in young children should develop new methodology to account for smaller foot size., (Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)