Effect of Al2O3-NbC nanopowder incorporation on the mechanical properties of 3Y-TZP/Al2O3-NbC nanocomposites obtained by conventional and spark plasma sintering

[EN] The incorporation of Al2O3-NbC-nanopowder reinforcement in a 3Y-TZP matrix, and its influence on the mechanical properties of 3YTZP/Al2O3-NbC nanocomposites, obtained by conventional and spark plasma sintering (SPS), was investigated. Nanometric powders of Al2O3-NbC were prepared by reactive high-energy milling, deagglomeration, and leaching with acid, and added to the 3Y-TZP matrix, at a proportion of 5 vol%. The final powders were dried under airflow, compacted, and sintered in the temperature range of 1300-1500 degrees C. The effects of the sintering technique and final temperature, on the microstructure and mechanical properties, such as hardness, toughness, and Young's modulus, were analysed. Fracture toughness of the material reinforced with Al2O3-NbC nanopowders, which is one of its most important properties, differed significantly from that of the 3Y-TZP monolith (5.2 MPa m(1/2)). The nanocomposites, sintered conventionally at 1450 degrees C, showed higher fracture toughness (8.7 MPa m(1/2)). Microstructure observations indicated that NbC nanoparticles were dispersed homogeneously within the 3Y-TZP matrix, and limited its grain growth. However, partial oxidation of the NbC on the nanocomposite surface, at the conventional sintering temperature of 1500 degrees C, caused a reduction in the fracture toughness.The authors acknowledge the Brazilian institutions CAPES-PVE (grant number 23038.009604/2013-12), FAPESP (grant number 2015/07319-8), Fundação Araucária (grant number 810/2014), European Union/Erasmus Mundus for doctorate mobility (grant number EB15DM1542), and the Spanish Ministry of Economy and Competitiveness (grant number IJCI-2014-19839).Salem, R.; Monteiro, R.; Gutierrez, CF.; Borrell Tomás, MA.; Salvador Moya, MD.; Chinelatto, AS.; Chinelatto, A.... (2018). Effect of Al2O3-NbC nanopowder incorporation on the mechanical properties of 3Y-TZP/Al2O3-NbC nanocomposites obtained by conventional and spark plasma sintering. Ceramics International. 44(2):2504-2509. https://doi.org/10.1016/j.ceramint.2017.10.235S2504250944

Dry-sliding wear behavior of 3Y-TZP/Al2O3-NbC nanocomposites produced by conventional sintering and spark plasma sintering

[EN] This work presents the initial results of the dry-sliding wear behavior of 3 mol% yttria-stabilized zirconia reinforced with 5 vol% alumina-niobium carbide (3Y-TZP/5 vol% Al2O3-NbC) nanocomposites sintered by conventional sintering and spark plasma sintering methods in the temperature range of 1350-1450 degrees C. The reinforcement of 3Y-TZP matrix with hard nanoparticles aimed to improve wear strength of the composites. Wear tests were performed by the ball-on-disc method using alumina (Al2O3) and tungsten carbide with 6 wt% cobalt cermet (WC-6%Co) balls as counter-materials, a load of 15 N, a sliding distance of 2000 m, and a sliding speed of 0.1 m/s. Wear behavior was evaluated in terms of wear rate and FE-SEM micrograph analysis of the wear tracks. The nanocomposite sintered at 1450 degrees C by conventional sintering exhibited the least wear when tested with the WC-6%Co ball. Generally, the wear mechanism showed evidence of severe wear regime with both counter-materials.The authors acknowledge the Brazilian institutions CAPES-PVE (grant number 23038.009604/2013-12), FAPESP (grant number 2015/07319-8), Fundação Araucária (grant number 810/2014), European Union/Erasmus Mundus for doctorate mobility (grant number EB15DM1542), and the Spanish Ministry of Economy and Competitiveness (RYC-2016-20915).Salem, R.; Gutiérrez-González, C.; Borrell Tomás, MA.; Salvador Moya, MD.; Chinelatto, AL.; Chinelatto, AS.; Pallone, E. (2019). Dry-sliding wear behavior of 3Y-TZP/Al2O3-NbC nanocomposites produced by conventional sintering and spark plasma sintering. International Journal of Applied Ceramic Technology. 16(3):1265-1273. https://doi.org/10.1111/ijac.13151S12651273163Liu, H., Zhao, W., Ji, Y., Cui, J., Chu, Y., & Rao, P. (2017). Determination of fracture toughness of zirconia ceramics with different yttria concentrations by SEVNB method. Ceramics International, 43(13), 10572-10575. doi:10.1016/j.ceramint.2017.04.064Ćorić, D., Majić Renjo, M., & Ćurković, L. (2017). Vickers indentation fracture toughness of Y-TZP dental ceramics. International Journal of Refractory Metals and Hard Materials, 64, 14-19. doi:10.1016/j.ijrmhm.2016.12.016De Aza, A. H., Chevalier, J., Fantozzi, G., Schehl, M., & Torrecillas, R. (2002). Crack growth resistance of alumina, zirconia and zirconia toughened alumina ceramics for joint prostheses. Biomaterials, 23(3), 937-945. doi:10.1016/s0142-9612(01)00206-xAragón-Duarte, M. C., Nevarez-Rascón, A., Esparza-Ponce, H. E., Nevarez-Rascón, M. M., Talamantes, R. P., Ornelas, C., … Hurtado-Macías, A. (2017). Nanomechanical properties of zirconia- yttria and alumina zirconia- yttria biomedical ceramics, subjected to low temperature aging. Ceramics International, 43(5), 3931-3939. doi:10.1016/j.ceramint.2016.12.033Balko, J., Csanádi, T., Sedlák, R., Vojtko, M., KovalĿíková, A., Koval, K., … Naughton-Duszová, A. (2017). Nanoindentation and tribology of VC, NbC and ZrC refractory carbides. Journal of the European Ceramic Society, 37(14), 4371-4377. doi:10.1016/j.jeurceramsoc.2017.04.064Alecrim, L. R. R., Ferreira, J. A., Gutiérrez-González, C. F., Salvador, M. D., Borrell, A., & Pallone, E. M. J. A. (2017). Effect of reinforcement NbC phase on the mechanical properties of Al2O3-NbC nanocomposites obtained by spark plasma sintering. International Journal of Refractory Metals and Hard Materials, 64, 255-260. doi:10.1016/j.ijrmhm.2016.10.021Alecrim, L. R. R., Ferreira, J. A., Gutiérrez-González, C. F., Salvador, M. D., Borrell, A., & Pallone, E. M. J. A. (2017). Sliding wear behavior of Al2O3-NbC composites obtained by conventional and nonconventional techniques. Tribology International, 110, 216-221. doi:10.1016/j.triboint.2017.02.028Santos, C., Maeda, L. D., Cairo, C. A. A., & Acchar, W. (2008). Mechanical properties of hot-pressed ZrO2–NbC ceramic composites. International Journal of Refractory Metals and Hard Materials, 26(1), 14-18. doi:10.1016/j.ijrmhm.2007.01.008Ünal, N., Kern, F., Öveçoğlu, M. L., & Gadow, R. (2011). Influence of WC particles on the microstructural and mechanical properties of 3mol% Y2O3 stabilized ZrO2 matrix composites produced by hot pressing. Journal of the European Ceramic Society, 31(13), 2267-2275. doi:10.1016/j.jeurceramsoc.2011.05.032Sequeira, S., Fernandes, M. H., Neves, N., & Almeida, M. M. (2017). Development and characterization of zirconia–alumina composites for orthopedic implants. Ceramics International, 43(1), 693-703. doi:10.1016/j.ceramint.2016.09.216Schmitt-Radloff, U., Kern, F., & Gadow, R. (2017). Wire-electrical discharge machinable alumina zirconia niobium carbide composites – Influence of NbC content. Journal of the European Ceramic Society, 37(15), 4861-4867. doi:10.1016/j.jeurceramsoc.2017.07.014Akatsu, T., Nakanishi, S., Tanabe, Y., Wakai, F., & Yasuda, E. (2013). Toughening enhanced at elevated temperatures in an alumina/zirconia dual-phase matrix composite reinforced with silicon carbide whiskers. Journal of the European Ceramic Society, 33(15-16), 3157-3163. doi:10.1016/j.jeurceramsoc.2013.05.029Lee, D.-J., Choi, H.-S., Jin, F.-L., & Park, S.-J. (2015). A study on mechanical properties and microstructure of tetragonal zirconia-based composites. Journal of Industrial and Engineering Chemistry, 27, 322-328. doi:10.1016/j.jiec.2015.01.008Salem, R. E. P., Monteiro, F. R., Gutiérrez-González, C. F., Borrell, A., Salvador, M. D., Chinelatto, A. S. A., … Pallone, E. M. J. A. (2018). Effect of Al2O3-NbC nanopowder incorporation on the mechanical properties of 3Y-TZP/Al2O3-NbC nanocomposites obtained by conventional and spark plasma sintering. Ceramics International, 44(2), 2504-2509. doi:10.1016/j.ceramint.2017.10.235Schmitt-Radloff, U., Kern, F., & Gadow, R. (2018). Spark plasma sintering and hot pressing of ZTA-NbC materials – A comparison of mechanical and electrical properties. Journal of the European Ceramic Society, 38(11), 4003-4013. doi:10.1016/j.jeurceramsoc.2018.04.022Pędzich, Z., Haberko, K., Faryna, M., & Sztwiertnia, K. (2002). Interphase Boundary in Zirconia – Carbide Particulate Composites. Key Engineering Materials, 223, 221-226. doi:10.4028/www.scientific.net/kem.223.221Acchar, W., Zollfrank, C., & Greil, P. (2004). Microstructure and mechanical properties of WC-Co reinforced with NbC. Materials Research, 7(3), 445-450. doi:10.1590/s1516-14392004000300012Guillon, O., Gonzalez‐Julian, J., Dargatz, B., Kessel, T., Schierning, G., Räthel, J., & Herrmann, M. (2014). Field‐Assisted Sintering Technology/Spark Plasma Sintering: Mechanisms, Materials, and Technology Developments. Advanced Engineering Materials, 16(7), 830-849. doi:10.1002/adem.201300409Munir, Z. A., Anselmi-Tamburini, U., & Ohyanagi, M. (2006). The effect of electric field and pressure on the synthesis and consolidation of materials: A review of the spark plasma sintering method. Journal of Materials Science, 41(3), 763-777. doi:10.1007/s10853-006-6555-2Lu, K. (2008). Sintering of nanoceramics. International Materials Reviews, 53(1), 21-38. doi:10.1179/174328008x254358Borrell, A., Fernández, A., Torrecillas, R., Córdoba, J. M., Avilés, M. A., & Gotor, F. J. (2010). Spark Plasma Sintering of Ultrafine TiCxN1−x Powders Synthesized by a Mechanically Induced Self-Sustaining Reaction. Journal of the American Ceramic Society, 93(8), 2252-2256. doi:10.1111/j.1551-2916.2010.03735.xBonache, V., Salvador, M. D., Fernández, A., & Borrell, A. (2011). Fabrication of full density near-nanostructured cemented carbides by combination of VC/Cr3C2 addition and consolidation by SPS and HIP technologies. International Journal of Refractory Metals and Hard Materials, 29(2), 202-208. doi:10.1016/j.ijrmhm.2010.10.007Gutiérrez-Mora, F., Cano-Crespo, R., Rincón, A., Moreno, R., & Domínguez-Rodríguez, A. (2017). Friction and wear behavior of alumina-based graphene and CNFs composites. Journal of the European Ceramic Society, 37(12), 3805-3812. doi:10.1016/j.jeurceramsoc.2017.02.024Wei, J., Lin, B., Wang, H., Sui, T., Yan, S., Zhao, F., … Fang, S. (2018). Friction and wear characteristics of carbon fiber reinforced silicon carbide ceramic matrix (Cf/SiC) composite and zirconia (ZrO2) ceramic under dry condition. Tribology International, 119, 45-54. doi:10.1016/j.triboint.2017.10.023Fan, H., Hu, T., Zhang, Y., Fang, Y., Song, J., & Hu, L. (2014). Tribological properties of micro-textured surfaces of ZTA ceramic nanocomposites under the combined effect of test conditions and environments. Tribology International, 78, 134-141. doi:10.1016/j.triboint.2014.05.010Gee, M., & Nunn, J. (2017). Real time measurement of wear and surface damage in the sliding wear of alumina. Wear, 376-377, 1866-1876. doi:10.1016/j.wear.2017.01.114Wang, Y., Yang, Y., Zhao, Y., Tian, W., Bian, H., & He, J. (2009). Sliding wear behaviors of in situ alumina/aluminum titanate ceramic composites. Wear, 266(11-12), 1051-1057. doi:10.1016/j.wear.2008.11.006Krell, A. (1996). Improved hardness and hierarchic influences on wear in submicron sintered alumina. Materials Science and Engineering: A, 209(1-2), 156-163. doi:10.1016/0921-5093(95)10155-1Botta F, W. ., Tomasi, R., Pallone, E. M. J. ., & Yavari, A. . (2001). Nanostructured composites obtained by reactive milling. Scripta Materialia, 44(8-9), 1735-1740. doi:10.1016/s1359-6462(01)00789-8Pallone, E. M. J. ., Trombini, V., Botta F, W. ., & Tomasi, R. (2003). Synthesis of Al2O3–NbC by reactive milling and production of nanocomposites. Journal of Materials Processing Technology, 143-144, 185-190. doi:10.1016/s0924-0136(03)00411-4ASTM G99‐03 Standard test method for wear testing with a pin‐on‐disc apparatus ASTM Annual Book of Standards vol.03. West Conshohocken PA;2003.Chen, W.-H., Lin, H.-T., Chen, J., Nayak, P. K., Lee, A. C., Lu, H.-H., & Huang, J.-L. (2016). Microstructure and wear behavior of spark plasma sintering sintered Al2O3/WC-based composite. International Journal of Refractory Metals and Hard Materials, 54, 279-283. doi:10.1016/j.ijrmhm.2015.07.030Espinosa-Fernández, L., Borrell, A., Salvador, M. D., & Gutierrez-Gonzalez, C. F. (2013). Sliding wear behavior of WC–Co–Cr3C2–VC composites fabricated by conventional and non-conventional techniques. Wear, 307(1-2), 60-67. doi:10.1016/j.wear.2013.08.003Bundschuh, W., & Gahr, K.-H. Z. (1991). Influence of porosity on friction and sliding wear of tetragonal zirconia polycrystal. Wear, 151(1), 175-191. doi:10.1016/0043-1648(91)90356-yBayer, R. J. (2004). Mechanical Wear Fundamentals and Testing, Revised and Expanded. doi:10.1201/9780203021798Zum Gahr, K.-H. (1989). Sliding wear of ceramic-ceramic, ceramic-steel and steel-steel pairs in lubricated and unlubricated contact. Wear, 133(1), 1-22. doi:10.1016/0043-1648(89)90109-9Kato, K., & Adachi, K. (2002). Wear of advanced ceramics. Wear, 253(11-12), 1097-1104. doi:10.1016/s0043-1648(02)00240-5Pasaribu, H. R., Sloetjes, J. W., & Schipper, D. J. (2004). The transition of mild to severe wear of ceramics. Wear, 256(6), 585-591. doi:10.1016/j.wear.2003.10.025Wang, S. W., Chen, L. D., Hirai, T., & Kang, Y. S. (1999). Journal of Materials Science Letters, 18(14), 1119-1121. doi:10.1023/a:1006684631127Muñoz, S., & Anselmi-Tamburini, U. (2012). Parametric investigation of temperature distribution in field activated sintering apparatus. The International Journal of Advanced Manufacturing Technology, 65(1-4), 127-140. doi:10.1007/s00170-012-4155-7Xiong, Y., Fu, Z. Y., Wang, H., Wang, Y. C., & Zhang, Q. J. (2005). Microstructure and IR transmittance of spark plasma sintering translucent AlN ceramics with CaF2 additive. Materials Science and Engineering: B, 123(1), 57-62. doi:10.1016/j.mseb.2005.06.02

A gap analysis of SDG 3 and MDG 4/5mortality health targets in the six Arabic countries of North Africa: Egypt, Libya, Tunisia, Algeria, Morocco, and Mauritania.

Bjegovic-Mikanovic V, Abousbie ZAS, Breckenkamp J, et al. A gap analysis of SDG 3 and MDG 4/5mortality health targets in the six Arabic countries of North Africa: Egypt, Libya, Tunisia, Algeria, Morocco, and Mauritania. The Libyan journal of medicine. 2019;14(1): 1607698.BACKGROUND: The United Nations Assembly adopted the Sustainable Development Goals to succeed the Millennium Development Goals in September 2015. From a European perspective, the development of health in the countries of North Africa are of special interest as a critical factor of overall social development in Europe's Mediterranean partners. In this paper, we address the mortality related SDG-3 targets, the likelihood to achieve them until 2030 and analyze how they are defined.; METHODS: We projected mortality trends from 2000-2015 to 2030, based on mortality estimates by inter-agency groups and the WHO in mother and child health, non-communicable diseases, and road traffic mortality. The gap analysis compares the time remaining until 2030 to the time needed to complete the target assuming a linear trend of the respective indicator. A delay of not more than 3.75 years is considered likely to achieve the target.; RESULTS: The SDG-3 targets of a Maternal Mortality Ratio below 70 per 100 000 live births and an U5MR below 25 per 1 000 live births have been achieved by Egypt, Libya, and Tunisia. Libya and Tunisia have also achieved the target for Newborn Mortality with Egypt close to achieving it as well. Algeria and Morocco are generally on track for most of the indicators, including deaths from non-communicable diseases and suicide rates; however, all of the countries are lagging when it comes to deadly Road Traffic Injuries for 2030. Mauritania is the only North African country which is not likely to reach the 2030 targets for any of the mortality indicators.; CONCLUSIONS: Although mortality statistics may be incomplete there is an impressive gradient from East to West showing Mauritania and deadly road traffic injuries as the most problematic areas. Given the large differences between countries baselines, we consider it preferable to set realistic targets to be achieved until 2030

Building the capacity of West African countries in Aedes surveillance: inaugural meeting of the West African Aedes Surveillance Network (WAASuN)

Arboviral diseases such as dengue, Zika and chikungunya transmitted by Aedes mosquitoes have been reported in 34 African countries. Available data indicate that in recent years there have been dengue and chikungunya outbreaks in the West Africa subregion, in countries including Côte d’Ivoire, Burkina Faso, Gabon, Senegal, and Benin. These viral diseases are causing an increased public health burden, which impedes poverty reduction and sustainable development. Aedes surveillance and control capacity, which are key to reducing the prevalence of arboviral infections, need to be strengthened in West Africa, to provide information essential for the formulation of effective vector control strategies and the prediction of arboviral disease outbreaks. In line with these objectives, the West African Aedes Surveillance Network (WAASuN) was created in 2017 at a meeting held in Sierra Leone comprising African scientists working on Aedes mosquitoes. This manuscript describes the proceedings and discusses key highlights of the meeting

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950–2021, and the impact of the COVID-19 pandemic: a comprehensive demographic analysis for the Global Burden of Disease Study 2021

Background: Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020–21 COVID-19 pandemic period. Methods: 22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. Findings: Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5–65·1] decline), and increased during the COVID-19 pandemic period (2020–21; 5·1% [0·9–9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98–5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50–6·01) in 2019. An estimated 131 million (126–137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7–17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8–24·8), from 49·0 years (46·7–51·3) to 71·7 years (70·9–72·5). Global life expectancy at birth declined by 1·6 years (1·0–2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67–8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4–52·7]) and south Asia (26·3% [9·0–44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations. Interpretation: Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic

The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

Global incidence, prevalence, years lived with disability (YLDs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

Background: Detailed, comprehensive, and timely reporting on population health by underlying causes of disability and premature death is crucial to understanding and responding to complex patterns of disease and injury burden over time and across age groups, sexes, and locations. The availability of disease burden estimates can promote evidence-based interventions that enable public health researchers, policy makers, and other professionals to implement strategies that can mitigate diseases. It can also facilitate more rigorous monitoring of progress towards national and international health targets, such as the Sustainable Development Goals. For three decades, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) has filled that need. A global network of collaborators contributed to the production of GBD 2021 by providing, reviewing, and analysing all available data. GBD estimates are updated routinely with additional data and refined analytical methods. GBD 2021 presents, for the first time, estimates of health loss due to the COVID-19 pandemic. Methods: The GBD 2021 disease and injury burden analysis estimated years lived with disability (YLDs), years of life lost (YLLs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries using 100 983 data sources. Data were extracted from vital registration systems, verbal autopsies, censuses, household surveys, disease-specific registries, health service contact data, and other sources. YLDs were calculated by multiplying cause-age-sex-location-year-specific prevalence of sequelae by their respective disability weights, for each disease and injury. YLLs were calculated by multiplying cause-age-sex-location-year-specific deaths by the standard life expectancy at the age that death occurred. DALYs were calculated by summing YLDs and YLLs. HALE estimates were produced using YLDs per capita and age-specific mortality rates by location, age, sex, year, and cause. 95% uncertainty intervals (UIs) were generated for all final estimates as the 2·5th and 97·5th percentiles values of 500 draws. Uncertainty was propagated at each step of the estimation process. Counts and age-standardised rates were calculated globally, for seven super-regions, 21 regions, 204 countries and territories (including 21 countries with subnational locations), and 811 subnational locations, from 1990 to 2021. Here we report data for 2010 to 2021 to highlight trends in disease burden over the past decade and through the first 2 years of the COVID-19 pandemic. Findings: Global DALYs increased from 2·63 billion (95% UI 2·44–2·85) in 2010 to 2·88 billion (2·64–3·15) in 2021 for all causes combined. Much of this increase in the number of DALYs was due to population growth and ageing, as indicated by a decrease in global age-standardised all-cause DALY rates of 14·2% (95% UI 10·7–17·3) between 2010 and 2019. Notably, however, this decrease in rates reversed during the first 2 years of the COVID-19 pandemic, with increases in global age-standardised all-cause DALY rates since 2019 of 4·1% (1·8–6·3) in 2020 and 7·2% (4·7–10·0) in 2021. In 2021, COVID-19 was the leading cause of DALYs globally (212·0 million [198·0–234·5] DALYs), followed by ischaemic heart disease (188·3 million [176·7–198·3]), neonatal disorders (186·3 million [162·3–214·9]), and stroke (160·4 million [148·0–171·7]). However, notable health gains were seen among other leading communicable, maternal, neonatal, and nutritional (CMNN) diseases. Globally between 2010 and 2021, the age-standardised DALY rates for HIV/AIDS decreased by 47·8% (43·3–51·7) and for diarrhoeal diseases decreased by 47·0% (39·9–52·9). Non-communicable diseases contributed 1·73 billion (95% UI 1·54–1·94) DALYs in 2021, with a decrease in age-standardised DALY rates since 2010 of 6·4% (95% UI 3·5–9·5). Between 2010 and 2021, among the 25 leading Level 3 causes, age-standardised DALY rates increased most substantially for anxiety disorders (16·7% [14·0–19·8]), depressive disorders (16·4% [11·9–21·3]), and diabetes (14·0% [10·0–17·4]). Age-standardised DALY rates due to injuries decreased globally by 24·0% (20·7–27·2) between 2010 and 2021, although improvements were not uniform across locations, ages, and sexes. Globally, HALE at birth improved slightly, from 61·3 years (58·6–63·6) in 2010 to 62·2 years (59·4–64·7) in 2021. However, despite this overall increase, HALE decreased by 2·2% (1·6–2·9) between 2019 and 2021. Interpretation: Putting the COVID-19 pandemic in the context of a mutually exclusive and collectively exhaustive list of causes of health loss is crucial to understanding its impact and ensuring that health funding and policy address needs at both local and global levels through cost-effective and evidence-based interventions. A global epidemiological transition remains underway. Our findings suggest that prioritising non-communicable disease prevention and treatment policies, as well as strengthening health systems, continues to be crucially important. The progress on reducing the burden of CMNN diseases must not stall; although global trends are improving, the burden of CMNN diseases remains unacceptably high. Evidence-based interventions will help save the lives of young children and mothers and improve the overall health and economic conditions of societies across the world. Governments and multilateral organisations should prioritise pandemic preparedness planning alongside efforts to reduce the burden of diseases and injuries that will strain resources in the coming decades. Funding: Bill &amp; Melinda Gates Foundation

Understanding the micro and macro politics of health: Inequalities, intersectionality & institutions-A research agenda

This essay brings together intersectionality and institutional approaches to health inequalities, suggesting an integrative analytical framework that accounts for the complexity of the intertwined influence of both individual social positioning and institutional stratification on health. This essay therefore advances the emerging scholarship on the relevance of intersectionality to health inequalities research. We argue that intersectionality provides a strong analytical tool for an integrated understanding of health inequalities beyond the purely socioeconomic by addressing the multiple layers of privilege and disadvantage, including race, migration and ethnicity, gender and sexuality. We further demonstrate how integrating intersectionality with institutional approaches allows for the study of institutions as heterogeneous entities that impact on the production of social privilege and disadvantage beyond just socioeconomic (re)distribution. This leads to an understanding of the interaction of the macro and the micro facets of the politics of health. Finally, we set out a research agenda considering the interplay/intersections between individuals and institutions and involving a series of methodological implications for research - arguing that quantitative designs can incorporate an intersectional institutional approach